1. Technical Field
The present invention relates to a reel around which a recording tape is wound.
2. Description of the Related Art
Recording tapes such as magnetic tapes are used as an external recording medium for computers and the like. Prevention of dust adhesion and a smaller storage space are preferred because the recording tapes are generally used for back-up of large volumes of information owing to their large recording capacities.
For the above reason, a recording tape cartridge with a case and a single reel around which a recording tape is wound and which is rotatably contained in the case is adopted. This type of cartridge can prevent adhesion of dust to the recording tape. In addition, this recording tape cartridge almost halves a storage space compared with a structure with a second reel for retracting the recording tape when recording or reproducing information recorded on the recording tape.
Among recording tape cartridges, a recording tape cartridge including a leader block fixed to a leading or free end of a recording tape directly or by a leader tape is known. The leader block is retained outwardly around an opening formed in the case for drawing the recording tape. The leader block functions both as an operational member for drawing the recording tape from the case, and as a blocking member for blocking the opening through which the recording tape is drawn.
This recording tape cartridge is loaded in a tape drive system when recording information on the recording tape or reproducing information recorded on the recording tape. In the drive system loaded with the recording tape cartridge, a drawing device operates the leader block to draw the recording tape from the case, and to guide the recording tape to a predetermined position on a tape path, thereby holding the leader block in the hub (reel hub) of a machine reel (take-up reel).
As shown in FIG. 17A, a leader block 106 has, at a longitudinal direction center thereof, a recess 100, in which the leading end of a recording tape 104 is fixed by a clamp pin 102. The leader block 106 is retained in an insertion portion 112 formed in a hub 110 of a machine reel 108 (hereinafter referred to as reel 108). An end of the leader block 106 positioned at an opening end of the insertion portion 112 has an arc-shaped, curved surface 116, which corresponds to a periphery 114 of the hub 110. The curved surface 116 of the leader block 106, together with the periphery 114, forms a retracting surface 118, which is substantially circular when viewed in an axial direction of the reel 108, for retracting the recording tape 104. Under these conditions, as the reel 108 (hub 110) of the drive system is rotationally driven, the recording tape 104 is wound on the retracting surface 118.
However, in the conventional leader block 106, the curved surface 116, which is formed at the longitudinal direction end thereof, and constitutes a portion of the retracting surface 118, has a short arc length. In other words, as shown in FIG. 17A, a projection xe2x80x9caxe2x80x9d, a projecting distance in a diametrical direction of the curved surface 116 from an edge of the opening of the insertion portion 112 is small. As a result, as shown in FIG. 17B, the curved surface 116 may be positioned within the insertion portion 112 without projecting from therefrom merely due to the leader block being slightly dislocated in the insertion portion 112.
In such an event, a fold or deformation may be formed on the recording tape 104 at the edge of the opening of the insertion portion 112. Folds will be similarly formed on subsequent layers of the recording tape 104 wound over the edge portion. The portions of the recording tape 104 where the folds are formed are substantially recording areas. Since the folded portions cannot maintain a proper distance from a recording-reproducing head during the process of recording or reproducing information, and such areas may cause generation of areas incapable of having information recorded thereon or loss of recorded information.
If the leader block 106 is slightly dislocated in the insertion portion 112 and the curved surface 116 protrudes from the periphery 114 of the hub 110, as shown in FIG. 17C, the recording tape 104 is wound with deformation at a larger curvature than a predetermined winding curvature, along the short area of the projected part (uneven portion) formed on the retracting surface 118 because the arc length of the curved surface 116 is short. Like the folds, such a deformation will deform the subsequent layers of the recording tape 104 wound over the projected part, thereby causing generation of areas incapable of having information recorded or loss of recorded information.
Even if a leader pin, rather than the leader block, is fixed to the leading end of the recording tape, a drawing device of the tape drive system operates the leader pin to draw the recording tape from the case, the leading end of the recording tape is fixed by a clamp portion of the hub, and the recording tape is wound by the rotation of the machine reel, the clamp portion will make an uneven portion and cause similar problems as mentioned above.
Moreover, even a reel contained in a case has a similar problem when the clamp member for clamping the leading end of the recording tape on the body of the hub is excessively inserted into the insertion portion of the hub or excessively projected out from the insertion portion to make an uneven portion.
In light of the foregoing, an object of the present invention is to provide a reel, which can prevent a recording tape from having an uneven portion, thereby preventing generation of an area incapable of having information recorded thereon or loss of recorded information.
The present inventor has noticed that even when an uneven portion is formed on a clamp portion, an uneven portion is not formed on the recording tape once the tape is wound to a certain number of layers. The reel is necessarily driven to wind the recording tape. The inventor has also conceived that the uneven portion can be removed during the driving of the reel, and thus completed the present invention.
According to the present invention, in a reel having a hub around which a recording tape is wound, a flexible member is attached to the hub. The flexible member is wound on the periphery of the hub by the recording tape to cover a clamp portion of the hub.
Because the flexible member is necessarily wound with the winding of the recording tape, the recording tape wound on the periphery of the flexible member does not come into contact with the clamp portion of the hub and consequently does not come into contact with the uneven portion formed at the clamp portion. Accordingly, it is possible to prevent occurrence of a tape deformation on the recording tape wound around the reel, thereby preventing generation of an area incapable of having information recorded thereon or loss of recorded information.